REPORTS 

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Canada  Consolidated  Gold  Mining  Company's 

PROPERTY 

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-    DELORO.  ONTARIO. 


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REPORTS 


ON  THE 


PRESENT  CONDITION 


OF  THE 


Canada  Consolidated  Gold  Mining  Company's 


PROPERTY 


AND  ON  THE  ' 


TREATMENT  OF  ITS  ORES 


AT 


DELORO,  ONTARIO. 


NEW  YORK: 

MARTIN     B.    BROWN,    PRINTER    AND    STATIONER. 

NOS.   49   AND  51    PARK  PLACE. 
1883. 


REPORT   OF 

RICHARD  P.  ROTHWELL, 


SUPERINTENDENT. 


To  the    Trustees   of   the    Canada   Consolidated    Gold   Mining 
Company : 

The  present  condition  of  the  company's  property  is  as  fol- 
lows :  No  work  has  been  done  by  the  company  on  any  of  the 
numerous  small  veins.  The  main  vein,  which  has  not  been 
worked  since  July,  1882,  is  opened  to  a  depth  of  170  feet,  and 
the  pay  chute  over  a  length  of  about  750  feet  by  shafts  and 
levels  aggregating  about  1100  feet  in  length.  The  ore  in  the 
vein  certainly  exceeds  an  average  thickness  of  eight  feet,  and 
probably  will  run  very  much  more  than  this.  The  quantity 
of  ore  in  sight  is  sufficient  to  supply  the  present  works  for 
several  years. 

The  mines  are  in  a  position  to  produce  100  tons  a  day.  The 
double  engines  and  boilers  for  permanent  hoisting-works — to 
hoist  from  two  shafts  from  a  central  point — are  on  the  ground 
(the  boilers  being  included  in  the  chattels  sold),  and  the 
friction-drums  are  being  made  in  Pennsylvania. 

The  tram-road,  with  its  iron  cars  for  taking  the  ore  from 
the  mines  to  the  mill,  is  in  good  order. 

The  concentrating  mill  has  a  proved  capacity  of  fully  100 
tons  in  20  hours,  crushed  to  a  maximum  size  of  1.^  mm.  As 
much  as  7  tons  an  hour  have  been  put  through. 

The  roasting  is  done  in  a  continuous  operation  without 
handling,  in  two  revolving  cylinders,    which  have  a  proved 


capacity  of  10  tons  concentrates  per  24  hours.  This  is  equal 
to  from  40  to  50  tons  of  ore  (varying  with  proportion  of  sul- 
phtarets  in  ore),  or  about  one  half  the  mill  capacity. 

The  chlorinating  and  filtering  capacity  is  about  10  tons 
per  day,  or  the  same  as  furnace  capacity. 

To  increase  the  roasting  and  chlorinating  capacity  to  20 
tons  per  day,  or  to  the  possible  mill  output,  Avould  cost 
from  $15,000  to  $18,000. 

The  entire  cost  of  treating  50  tons  of  ore  per  day  is  given 
as  follows.  In  this  I  have  counted  wages  at  $1.50  per  day, 
which  cost  us  from  $1,25  to  $1.40  ;  and  wood  at  $2.50  per 
cord,  while  we  believe  it  can  be  purchased  in  winter  and 
delivered  for  $2.  I  have  also  added  one  man  per  shift  to  the 
mill,  and  one  to  each  shift  in  the  roasting  and  chlorinating, 
more  than  are  necessax'y  for  the  Avork.  Ako,  the  quantity  of 
wood  is  based  on  the  consumption  of  green  wood,  mostly 
basswood,  which  has  recently  been  the  only  wood  at  our 
command. 

Ebtimatk  op  Cost  (based  on  actual  work  done)  of  Milling,  Roasting, 

CULOniNATlNO,    ETC.,    AT  DELORO,   OnT. 

Fifty  tons  per  day. 
LOADING  AND  HAULING  from  mines  to  mill  (one  sliift,  10  hours)— 


8  men,  at  $1.50  each %i  m 

LN.  B.— Wlien  mines  are  worliing,  this  will  be  done  by  two  boys.] 
oil,  repairs,  etc  .jO 


PER  DAY.  PER  TON, 

CRUDE   ORB. 


$5  00  $0  10 

MILLING  (one  shift,  10  hours)— 

7  men  In  mill,  at  $1.50  each $10  50 

1  foreman,  at  $2  2  00 

1  fireman,  at  $1.75 1  75 

1  engineer,  at  $2 2  00 

4  cords  wood,  at  $2.50  per  cord 10  00 

Oil,  repairs,  etc 3  75 


$:J0  00  60 

BOASTING  (10  tons  concentrates  pt-r  24  hours)- 

4  men,  hoisting,  feeding,  etc.,  at  $1.60  each $6  W) 

aflremen,  at  $1.75  3  50 

Half  time  of  2  foremen,  at  $2.25 2  25 

1  fireman  (steam  at  night) 1  75 

6  cords  wood,  at  $2.50  per  cord 15  00 

Oil,  light,  etc 1  50 

$80  00  60 


5 

CHLORINATION,  PHECIPITATION,  ETC- 

8  men  at  $l.r)0 $18  00 

Half  time  of  2  foremen ' . .  [ .,25 

ChemiHt "'  .'^... "'.".'.'.""''  300 

Chloride  lime,  550  llw.,  at  ac  per  lb 1100 

Sulph.  acid,  000  Ibw.,  at  d>,c  per  lb .'..]  15  00 

Assay  materials,  precipitants,  light,  etc .........!..!""  435 

$47  50  $0  85 

Office  expenses,  superintendent,  repairs,  etc 12  50  25 


$2  60 


Mr.  Koerner,  then  Acting  Superintendent,  reported  the 
actual  expenses  during  the  last  week  in  November,  as  fol- 
lows : 

TiiK  Canada  Consolidated  Gold  Mining  Company,  I 
Deloko,  Ont.,  January  26,  1883.  ) 

To  R.  P.  RoTUWEi.L,  Superintendent : 

Deak  Siu  :  Below  please  find  report  in  reference  to  the  last  week's  work  in  Novem- 
ber, after  which  the  frost  shut  us  down.  I  may  mention  that  the  putting  in  of  the 
rolls  and  repairs  of  old  ones  occupied  from  October  30th  to  November  21  st,  so  that  the 
week  before  the  frost  came  on  was  the  only  week  for  work  I  had  : 

Loading  ore ^gp  Oq 

Mill  expenses 168  00 

Furnace  expenses  (including  chlorination) 78  00 

Cutting  and  hauling  wood ""       ]0»  00 

Acid  and  lime 110  00 

Ttr    u-        u  ^^^"^^ 

Macbme-shop tir  00 

$050  00 

Though  the  last  item  does  not  strictly  belong  to  it,  as  it  was  on  other  work  (con- 
struction account). 

Number  of  tons  put  through  the  mill  and  concentrated,  270. 
After  the  above  week's  work,  the  frost  shut  every  thing  up. 

Veiy  truly, 

F.  KOERNER, 

Acting  Superintendent. 

The  total  pay-roll  during  November,  is  reported  by  the 
treasurer  at  $3655.01.  The  above  was  so  much  of  it  as 
applied  to  treatment  of  the  ore  during  the  one  week's  run. 

These  items  amount  to  $2.41  per  ton ;  adding  repairs, 
office   expenses,  superintendent,  and   all  other  extras,  esti- 


mated  very  liberally  at  $100  during  the  week,  and  the  total 
cost  v.ould  be  but  $2.78  per  ton. 

The  above  figures  are  believed  to  be  perfectly  safe,  and,  as 
justified  by  actual  work,  many  of  the  items  are  even  excessive. 
If  but  40  tons  of  fcrude  ore  produced  10  tons  roasted  concen- 
trates, the  total  cost  of  treatment  would  be  about  $3  per  ton- 

The  mill  has  treated,  since  it  was  started,  but  800  tons  of 
crude  ore,  a  portion  only  of  which  was  concentrated.  The 
following  is  a  statement  of  the  result : 


Roasted  Ore. 

Total 
Value. 

Average 

Value 

Tailings. 

Total  Value 
Tailings. 

Net  Gold 

Obtained  in 

Solution. 

Per- 
cent- 

Tons. 

Average 

Value 

PER  Ton. 

age  Ex- 
tract- 
ed. 

16Ji 

47 
59 

$20  14 
88  69 
55  58 
24  11 

$337  29 

635  50 

2,611  m 

1,422  49 

$2  63 
2  t8 
2  67 
1  41 

$1  95 
45  21 
not 

144  04 
59  67 
97  16 
78  91 

$292  15 

579  93 

2,514  67 

1,344  86 

86-94 
91'24 
96-28 
94-54 

142^ 

1 

6 

26 

$85  19 
45  21 
34  21 
24  11* 

$5,007  11 

45  21 

205  11 

*fi02  7*. 

$277  68 
45  21 
assayed. 

u 

$4,731  61 

94-80 

174>^ 

$5,860  18 

Each  ton  of  these  tailings  was  assayed  separately.  Sum- 
marizing, we  find  that  the  chlorination  which  at  first  yielded 
86*94  per  cent  improved  as  work  progressed,  and  especially 
as  the  ore  was  concentrated  closer,  until  it  reached  96  28  per 
cent  as  the  average  of  47  tons,  having  an  av^  oge  value  of 
$55.58  per  ton.  It  will  be  noted  above  that  one  ton  by 
some  oversight  was  not  chlorinated  (probc.oly  was  badly 
roasted,  as  was  sometimes  found  to  be  the  case  before  the 
second  furnace  was  built),  and  was  thrown  out  in  the  tail- 
ings.   Omitting  this  one  ton,  the  average  of  142^^  tons  assayed 

♦  Estimated. 


7 

gave  an  average  value  of  $35.20  per  ton ;  tailings,  an  average 
of  $1.95;  percentage  extracted  and  obtained  in  the  liquor, 
94-50  per  cent.  This  is  considered  highly  satisfactory  for 
the  commencement  of  work.  In  addition  to  the  above  1431 
tons,  of  which  we  have  the  assays  of  both  ore  and  tailings, 
there  were  assayed  and  chlorinated  six  tons,  average  value 
$34.21  per  ton— total,  $205.11,  but  of  which  the  tailings  have 
not  yet  been  assayed.  Also,  25  tons  chlorinated,  of  which  no 
assays  have  yet  been  made,  but  which  are  estimated  to  aver- 
age the  same  as  the  preceding  59  tons,  namely,  $24.11  per  tou' 
There  are  also  67  tons  of  roasted  ore  on  hand,  which  may  run 
the  same  as  the  59  tons  last  assayed,  but  which,  for  greater 
safety,  I  count  at  $20  per  ton,  and  18  tons  raw  ore  ready  to 
roast,  counted  safely  at  $15.  There  is  also  a  quantity  of  dust 
in  the  chambers,  some  ore  lying  about  the  mill,  etc.,  all  esti- 
mated at  $250.     The  whole  summarizes  as  follows  : 

174J4  tons  chlorinated,  contained $5  860  18 

67       "     roasted,  not  yet  chlorinated,  estimated  at  $80  per  ton 1,,340  00 

18       "     raw  ore  estimated  at  $15  per  ton 270  00 

Dust  in  chambers,  ore  about  mill,  etc,  estimated 250  00 

Total.  $9.65  per  ton  of  crude  ore  milled,  or $7,720  18 

From  the  above  we  see  that,  after  deducting  the  heavy 
losses  always  incident  to  starting  new  works  with  men  who 
never  had  any  experience  in  the  work,  there  have  been 
obtained  in  the  roasted  ore  about  $9.65  per  ton  of  crude  ore. 
The  loss  in  concentrating  has  been  heavy,  though  we  have  as 
yet  no  exact  measure  of  it — not  having  the  means  to  do  every 
thing  we  desired  or  considered  necessary. 

We  have  about  forty-five  tons  of  crude  arsenic  on  hand. 
This  I  had  analyzed,  and  find  it  contains  about  97  per 
cent  of  pure  arsenious  acid.  This  is  remarkably  pure,  and, 
with  refining,  will  produce  a  very  exceptionally  valuable 
product.  This  arsenic  has  a  present  net  value  of  about  $20  a 
ton,  or  fully  $1  per  ton  of  ore  milled.  When  re-sublimed,  this 
net  value  will  be  nearly  doubled. 


8 

The  above  results  may  be  summarized  in  the  following 
table,  which  shows  a  fair  estimate,  based  upon  actual  expe- 
rience, of  the  profits  obtainable  in  working  this  ore  : 

Pkr  ton 
Cbudb  orb. 
Net  amount  of  gold  per  ton  of  ore  ns  mined,  which  is  obtained  in  roasted  ore,  that 

is,  after  deducting  losses  in  concentrating,  handling,  roasting,  etc . .  $'J  65 

i<M  loss  In  chlorlnntlon,  5  per  cent.  $0  48 

i««s  loss  in  precipitation,  say  3  per  cent 37 

75 

$8  90 

Jiet  amount  ol  gold  obtainable $8  80 

Net  value  of  crude  arsenic 1  00 

$9  90 
Cost  of  treatment 3  00 

Net  profit  realizable  per  ton,  treating  40  tons  per  day,  say $6  90 

Net  profits  realizable,  milling  fifty  tons  per  day,  $7.40  per  ton. 

These  figures  do  not  take  account  of  the  cost  of  mining, 
which  will  be  about  $2.50  per  ton  ;  but  this  will  probably  be 
balanced  by  the  reduced  loss  in  concentrating,  the  saving  of 
two  per  cent  in  chlorinating,  and  the  greater  profit  from 
refining  the  arsenic,  so  that  the  final  results  may  be  counted 
as  above. 

With  a  treatment  of  only  40  tons  a  day,  the  net  earnings 
should  then  be  $275  per  day,  or  with  50  tons,  $370  pe^'  day, 
or,  say,  $9500  per  month,  and  for  an  expenditure  of  say, 
$18,000,  this  output  can  be  doubled,  and  arsenic  refining- 
works  completed. 

The  bullion  actually  produced  has  been  only  $2148.65, 
and  it  represented  in  the  above  table  $3684  gold  in  the 
chlorine  liquor,  or,  allowing  3  per  cent  loss  in  precipitation, 
say,  $3584,  that  should  have  been  obtained.  Of  this  difference, 
a  certain  amount  will  yet  be  recovered  from  some  rich  tailings 
from  rechlorination  of  precipitate  ;  gold  in  crucible  bottoms, 
in  slag,  etc.  The  loss,  which  has  been  enormous,  was  proba- 
bly due  to  careless  handling,  some  leaks  in  new  tanks,  imper- 
fect precipitation  by  sulphate  of  iron,  and  losses  in  melting. 
That  they  are  not  unavoidable  is  shown  by  tlie  several  well- 


9 

known  experts,  to  whom  the  question  was  submitted  and 
whose  reports  are  appended. 

The  precipitation  of  the  -gold  by  filtration  through  char- 
coal appears  to  be  entirely  successful,  and  there  are  now 
some  $1800  in  the  charcoal.  The  experts  generally,  how- 
ever, prefer  precipitation  by  sulphide  of  hydrogen. 

I  beg  to  refer  to  these  expert  repor'"s,  but  for  con- 
venience summarize  them  as  follows  • 

Expert  Tests  on  the  Precipitation  of  Gold  from  this  Chloride 

Solution. 

Mr.  William  E.  Gifford,  chemist,  finds  that  AjS  precip- 
itated '0682  grm.  gold  per  liter  of  solution.  Ferrous  sul- 
phate, the  same  amount.  That  is  the  whole  of  the  gold  in  the 
solution.  Some  lime  was  also  precipitated  with  the  gold  by 
the  ferrous  sulphate.  Charcoal  also  precipitated  the  whole  of 
the  gold  without  other  substances. 

Professor  Koenig  found  ferrous  sulphate  precipitated  -069 
grm.  gold  per  liter  (threw  down,  also,  some  lime).  Hydro- 
gen sulphide,  -0728  grm.  gold  per  liter.  ACl  and  ferrous 
sulphate  practically  same  amount.  The  whole  of  the  gold 
seems  to  be  precipitated  by  these  methods.  Professor  Koenig 
prefers  an  aqueous  solution  of  hydrogen  sulphide. 

Mr.  N.  E.  Riotte,  metallurgist,  New  York,  finds  that  hydro- 
gen sulphide  in  gaseous  form  is  much  better  than  ferrous  sul- 
phate, which  latter  he  finds  does  not  precipitate  all  the  gold. 
Though  the  mines,  the  mill,  the  roasting- works,  and  the 
clorination  are  all  fully  as  satisfactory  as  was  ever  claimed 
for  them,  and  the  cost  of  treatment  even  with  wages  and 
materials  far  higher  than  when  our  estimates  were  made 
three  years  ago  is  scarcely  higher  than  the  figures  then  given, 
yet  the  time  occupied  in  bringing  the  property  into  a  divi.iend- 
paying  condition  has  been  far  longer  than  anticipated,  and 
the  working  capital  necessarily  increased  in  proportion. 

No  one  can  be  more  painfully  aware  than  myself  of  the 


10 

difficulties  and  disappointments  that  have  been  the  causes  of 
this,  and  I  desire  here  to  state  a  fact  well  known  to  those  of 
your  officers  and  others  familiar  with  the  case,  that  the  cost 
of  and  time  occupied  in  the  work  done  within  the  past  eight 
months  have  been  nearly  double  what  they  should  and  would 
have  been  had  the  stockholders  promptly  responded  to  the 
urgent  appeals  of  their  trustees  and  subscribed  for  the  bonds 
when  they  were  issued ;  indeed,  the  work  during  the  past 
year  has  been  carried  on  under  extremely  humiliating  and 
expensive  conditions,  that  probably  no  amount  of  salary  alone 
would  induce  any  one  to  submit  to. 

The  company  has  had  a  most  devoted  and  faithful  servant 
in  Mr.  F.  Koerner,  Master  of  Machinery,  who  acted  as  super- 
intendent during  my  absence  in  Europe.  Much  of  the  success 
of  our  concentrating  and  roasting-works  is  due  to  him.  He 
has  devotedly  remained  at  his  post  under  most  disagreeable 
and  unremunerative  conditions,  which  also  were  such  that 
professionally  he  could  not  do  himself  justice. 

The  chlorination  department  was  under  the  charge  of  the 
company's  chemist,  Mr.  Wilkins  U.  Green.  Had  the  preci- 
pitation of  the  gold  been  as  perfect  as  the  chlorination, 
this  department  would  have  had  a  more  satisfactory  record, 
and  the  condition  of  the  company  would  to-daj-  have  been 
very  different  from  what  it  is. 

I  also  desire  to  express  my  appreciation  of  the  devotion 
and  forbearance  of  our  foremen,  and  many  of  the  rank  and  file 
of  our  employes  at  Deloro,  who  continued  working  when  the 
company  already  owed  them  some  months'  pay,  and  who, 
convinced  of  the  ultimate  success  of  our  enterprise,  are  now 
waiting  patiently  for  the  resumption  of  work  and  the  liquida- 
tion of  their  just  claims. 

EICHAED  P.  ROTHWELL, 

Superintendent. 


11 


REPORT  OF  MR.  F.  KOERNER,  MASTER  OF 
•  MACHINERY. 

Wilkes-Barre,  Pa.,  February  10,  1883. 
R.  P.  RoTiiwELL,  Esq.,  Superim^ndent: 

Dear  Sir  :  In  compliance  with  your  request  for  a  resume  of  the  work 
at  Deloro,  as  far  as  it  was  under  my  cliarge,  I  submit  as  follows : 

After  the  new  mill  was  started,  toward  the  end  of  April  last,  and  ore 
ground,  it  was  found  that  it  could  not  be  roasted,  for  the  reason  that  no 
draught  could  be  made  through  the  furnace  and  arsenic  chambers  ;  in  fact, 
after  several  weeks'  trial,  the  attempt  had  to  be  given  up  and  an  exhaust-fan 
put  up  to  make  the  necessary  draught. 

With  the  fan  in  operation,  it  was  found  that,  while  a  small  quantity  of 
ore  could  be  I'oasted  in  the  furnace,  the  draught  had  necessarily  to  be  so 
sharp,  owing  to  the  smallness  of  the  openings  in  the  arsenic  chambers,  that 
most  of  the  arsenic,  instead  of  being  lodged  in  the  chambers,  was  carried 
through  the  fan  and  up  and  out  of  the  chimney  and  lost.  "When  the  fact 
that  the  fan  exerted  a  pull  of  five  eighths  of  an  inch  water-gauge  is 
remembered,  an  idea  of  the  friction  of  the  air  may  be  formed. 

Besides  tlie  loss  of  t!ie  arsenic,  the  fierceness  of  the  draught  carried 
fully  40  per  cent  of  the  ore  back  out  of  the  roasting  cylinder  into  the  dust- 
chambers. 

These  causes  made  it  necessary  to  stop  all  the  work  of  grinding  ore  and 
roasting,  fend  remodel  the  chambers.  This  was  done  by  cutting  the  openings 
from  one  chamber  to  the  other  down  to  the  floor,  and  also  by  making  an 
extra  opening  in  the  cross-division  wall  of  each  chamber. 

These  changes  were  found  effective,  and  were  completed  by  the  end  of 
July  last,  when  the  boiler-house  at  the  new  mill  took  fire  on  August  6th. 
The  necessary  repaira  of  pipes  and  connections  occupied  three  weeks. 

In  the  mean  time,  gearing  had  been  applied  to  the  Cornish  rolls,  and 
their  work  became  very  successful.  We  were  also  ejecting  the  masonry  and 
brick-work  for  an  additional  roasting-fumace,  which,  when  completed, 
toward  the  end  of  October,  gave  us  entire  control  of  the  ore  roasting,  with 
a  capacity  of  ten  tons  daily. 

It  was  then  found  that  it  had  become  necessary  to  complete  the  putting 
in  of  the  mill  machinery  by  adding  one  No.  2  screen  and  putting  in  the 
second  set  of  Cornish  rolls  and  one  new  jig.  After  these  additions,  or  rather 
after  completing  the  mill  so  far,  it  was  found  that  it  would  grind,  screen, 
and  concentrate  the  ore  at  the  rate  of  from  six  to  seven  tons  per  hour,  and 
that  the  furnaces  would  successfully  roast  the  resulting  concentrates. 


12 

We  had  by  this  time  readied  the  beginning  of  December  last.  The 
weather  kept  continuously  so  cold — as  low  as  20  degrees  below  zero,  Fahr- 
enheit— tliat  furtl^er  work  in  the  mill  became  impossible.  Having  arrived 
at  tliis  point,  that  is  to  say,  when  we  could  roast  ten  tons  of  concentrates, 
worth  on  an  average  from  SOO  to  $70  per  ton,  it  was  found  that  the  lime 
in  the  gold  solution  made  the  precipitation  of  the  gold  so  difficult  that  only 
a  few  tons  could  be  daily  chlorinated. 

Legal  complications  forced  us  to  suspend  work  entirely,  as  to  chlori- 
nation  and  roasting,  for  several  weeks. 

The  substitution  of  charcoal  filters  for  the  ordinary  process  of  precipi- 
tation by  iron  sulphate  seemed,  toward  the  end  of  December  and  beginning 
of  January,  to  promise  a  way  out  of  the  difficulty. 

Wiiile  it  can  not  be  denied  tiiat  a  great  deal  of  work  has  been  done  at 
Deloro,  and  many  difficulties  overcome,  much  more  would  certainly  have 
been  done  but  for  the  want  of  money.  During  the  summer  months,  with 
new  railroads  building  all  around  us,  and  the  wages  of  our  men  in  arrears, 
we  were  often  so  short  of  the  necessary  laborers  that  mortar-making,  ore- 
loading,  mill-work,  etc.,  had  to  be  done  in  rotation  by  the  same  men;  and, 
worae  than  that,  the  men's  wages  being  in  arrears,  they  worked  for  us  as  a 
favor,  as  it  were,  and  disciplftie  became  exceedingly  difficult,  if  not  im- 
possible. 

But  the  want  of  money  affected  the  lousiness  as  seriously,  to  say  the  least, 
in  other  ways.  When  the  mason  work  for  the  new  roaster  was  ready  and 
every  thing  else  complete,  the  roaster  itself  could  not  be  put  in  place  for 
want  of  tlie  necessary  outside  rings  and  castings  which  were  lying  at  the 
railway  station  at  Sterling,  and  could  not  be  got  for  want  of  money  to  pay 
the  freight.     Three  weeks  were  lost  with  tliis  single  item. 

The  pipes  for  heating  the  mill  and  by  that  enabling  us  to  go  on  working 
and  producing  at  least  $2000  profits  per  week,  were  lying  in  the  Custom- 
House  at  Belleville ;  but  there  was  no  money  to  pay  the  charges. 

I  am  writing  this  on  a  bed  of  sickness,  in  the  intervals  when  I  am  free 
from  pain,  and  I  am  aware  that  my  report  is  not  as  full  as  it  should  be  and 
would  have  been  under  other  circumstances. 

Resiiectfully  submitted, 

(Signed)        F.  KOERNER, 

Master  of  Machinery. 


i;{ 


REPORT   OF  Fxl.  WILKIiNo   U    GREENE,    r!HE^,IT j^T. 

The  Canada.  Consolidated  Goi,d  Mining  Company,  ) 
DELono,  Ont.,  January  29,  1883.  ,  \ 

R.  P.  RoTiiv^T-L,  Esq.,  Superintendent: 

Dear  Sik  :  In  your  communication  of  tlie  27th  inst.,you  guested  me 
to  make  a  report,  as  cliemist  to  this  company  from  July  24.,u,  Jie  time  I 
entered  on  tliat  position,  to  the  present  date. 

I  was  cngajjjed  by  tlie  company  through  you  as  chemist  and  assayer, 
but  was  never  placed  in  charge  of  the  chlorination  department.  After  I  had 
been  here  a  short  time,  on  tlie  absence  of  Henry  Bost,  I  started  to  run  the 
chlorlnator,  and  have  since  continued  in  tliat  capacity. 

As  you  well  know,  the  lime  that  occurs  in  the  ore  has  been  a  source 
of  endless  trouble,  as  most  precipitants  of  gold  would  precipitate  the  lime 
also.  In  order  to  separate  the  lime  from  the  gold,  several  methods  have 
been  tried. 

First.  On  experimenting,  I  found  that  sulphuric  acid  would  crystallize 
the  lime  out  of  the  gold  solution,  so  solutions  from  several  tons  of  ore  were 
treated  with  sulphuric  acid,  and  the  lime  allowed  to  crystallize  out;  the 
gold  solution  was  then  drawn  off,  and  tlie  gold  precipitated  with  sulphate 
of  iron.  But  still  some  lime  was  found  with  the  gold,  due  to  the  sulphuric 
acid  not  affecting  some  hyposulphate  of  lime  which  was  in  the  gold 
solution. 

By  tliis  method  most  of  the  gold  was  extracted  up  to  the  time  you 
sailed  for  Europe. 

As  the  quantity  of  sulphuric  acid  required  to  precipitate  or  rather 
crystallize  the  lime  was  large,  it  was  thought  advisable  to  try  some  other 
process. 

On  my  return  from  New  York,  after  you  left,  I  continued  chlorinating. 
The  gold  solution  accumulated,  tilling  all  the  tank-room,  before  I  could 
discover  the  best  method  to  try  next.  As  I  would  have  to  stop  chlorinating 
if  some  of  the  solution  was  not  removed,  and  as  stopping  w?,d  against  the 
orders  of  Mr.  Loveridge  or  Mr.  Koerner,  I  tried  the  following  method  ; 

At  this  point  I  wish  to  say  that  I  had  commenced  on  my  return  to  carry 
out  your  orders  in  regard  to  keeping  the  liquor  for  a  certain  number  of  tons 
separate  in  a  tank ;  but  as  the  tank-room  was  full,  and  having  no  means  of 
getting  rid  of  the  liquor  from  each  tank  by  itself,  I  was  obliged  to  use  the 
following  process : 

To  a  tank  of  solution  was  added  sulphate  of  iron  until  a  very  small 
quantity  of  gold  was  precipitated,  and  nearly  all  the  lime  as  a  sulphate. 
This  was  allowed  to  settle  ;  the  solution  containing  the  gold  was  placed  in 
another  tank,  and  sulphate  of  iron  added. 


14 

Into  the  tank  containing  the  lime  and  a  little  gold,  more  gold  solution 
was  placed,  which  dissolved  the  gold  already  in  the  tank,  and  the  same  pro- 
cess was  repeated.  My  intention  was  to  make  a  filter  Ijelow  these  lime-tanks, 
and  after  dissolving  the  gold  from  the  lime,  to  filter  tlie  gold  solution  which 
might  be  with  the  lime,  wash  it  and  throw  it  away;  in  this  manner  get  rid  of 
the  lime.  But  the  necessary  supplies  to  make  this  filter  I  applied  for  and  they 
were  promised  me,  but  never  sent.  Tiiis  left  me  in  a  very  bad  position,  as, 
when  the  process  was  given  up,  it  left  tliree  tanks  half  full  of  lime  holding 
some  gold.  Tlie  process  •would  have  l)een,  I  tliink,  a  success  if  I  could  have 
carried  it  out  as  I  desired  to,  but  I  was  ordered  by  Mr.  Koerner  to  get  a  brick 
out  in  a  week's  time.  In  order  to  do  this,  I  had  to  precipitate  all  tlie  liquor 
which  had  not  been  treated  as  above  with  sulphate  of  iron,  and  rechlorinate 
the  bulky  precipitate  thus  produced.  Of  course,  this  time,  as  before,  I  was 
unable  to  make  a  clean-up,  owing  to  the  gold  in  the  tanks  with  the  lime 
which  I  had  not  time  to  separate. 

As  in  rechlorination  some  lime  went  through  the  filters,  some  of  the 
strong  gold  solution  was  left  in  the  tank  and  was  afterward  passed  through 
the  charcoal  filters. 

On  or  about  November  21st,  1882,  at  the  one  hundred  and  thirty-seventh 
ton  chlorinated,  the  charcoal  filters  were  started,  which,  I  was  told  by  Mr. 
Loveridge,  was  an  experiment  made  by  the  company  and  not  by  me.  The 
liquors  from  chlorination  have  been  since  passed  through  them. 

In  order  to  get  the  gold  which  was  in  tlie  tanks  I  spoke  of,  with  the 
precipitated  lime,  I  was  obliged  to  pump  some  gold  solution,  strong  in  chlor- 
ine and  stir  the  lime  up  with  it,  as  by  tliis  means  the  precipitated  gold  would 
be  dissolved.     Tlie  lime  was  then  allowed  to  settle  and  the  gold  solution 

taken  off  and  passed  through  the  charcoal  filters.     The  remaining  lime  was 

placed  on  a  filter  and  washed  till  no  gold  showed  itself. 

The  charcoal  filters  seem  to  have  done  very  good  work,  precipitating  the 

gold  and  not  the  lime;   very  strict  watch  lias  been  kept  on  them  night  and 
day. 

About  .January  10th,  the  eight  upper  barrels  of  the  filter  were  taken  down 

and  replaced  by  fresh,  ones  that  the  gold  might  be  extracted.     This  charcoal 

was  started  burning  on  January  26th,  1883. 

It  was  my  desire  through  all  this  time,  covering  a  period  of  six  months, 

to  make  a  complete  clean-up,  in  order  to  ascertain  how  the  bullion  and  assays 

agreed;  but  as  I  received  orders  to  get  a  brick  out  in  such  a  limited  time  I 

was  unable  to  do  so,  much  to  my  regret.     I  am  sure  it  would  have  saved  the 

company  more  than  it  has  cost  them. 

Tliere  have  been  several  channels  tlirough  which  solut>ion  has  been  and 

might  have  been  lost. 

One  or  two  of  the  tanks  had  been  lined  with  very  thin  lead,  and  others 

with  very  poor  Icarl,  througli  which  the  solution  wo uhVeat  holes  and  thereby 

a  loss  would  occur  ;    all  of  which  was  repaired  as  soon  as  discovered.     Tiie 

rubber  hose,  which  was  used  to  convey  the  solution  from  the  filter  to  the  col- 


15 

lecting  tanks,  was  very  poor,  three-ply  pipe.  It  would  crack  and  holes 
appeared  in  it.  I  asked  for  some  other,  better,  explaining  the  great  neces- 
sity uf  it,  but  it  was  never  supplied. 

In  regard  to  the  assays  and  sampling:  Every  200  pounds  was  sampled 
and  the  samples  from  each  ton  assayed  (duplicated).  By  referring  to  the  assay- 
book,  you  will  see  that  in  some  cases  the  duplicates  disagreed  greatly  on 
account  of  coarse  gold:  an  average  was  taken,  of  course.  That  average 
might  have  been  too  high  or  too  low  in  many  cases.  Mr.  Santa  Maria's  assays 
were  done  by  mixing  three  tons  together  (samples),  which  I  do  not  think 
would  give  correct  results,  as  they  were  in  the  richest  concentrates  containing 
coarse  gold,  and  would  differ  considerably.  These  would  make  the  results 
of  the  assays  differ  from  tlie  bullion  extracted.  I  have  been,  during  my  stay 
here,  under  orders  from  yourself,  Mr.  Koerner,  and  Mr.  Loveridge,  which  in 
many  cases  have  conflicted  with  each  other,  placing  me  in  a  very  undesirable 
position.  I  have  endeavored  as  far  as  possible  to  have  the  approval  of  one 
of  the  above-named  to  every  detail  of  working  I  have  undertaken. 

Yours  respectfully, 

(Signed)  WILKIN S  U.  GREENE. 


CHEMISTS'   REPORTS  UPON    THE   PRECIPITATION 
OF  GOLD  FROM  CH.LORIDE   SOLUTION. 

R.  P.  RoTHWELL,  M.E.,  Superintendent  : 

SiH  :  Having  examined  the  sample  of  gold  solution  from  chlorination  of 
ore,  received  from  you  February  3d,  I  will  endeavor  to  answer  the  questions 
there  put  to  me  : 

First.  Whether  sulphureted  hydrogen  will  precipitate  all  the  gold  free 
from  other  substances,  and  at  what  cost  ? 

(The  question  being  raised  wliether  the  ordinary  reagents  precipitate  all 
the  gold  from  this  particular  solution,  it  was  obviously  inadmissil>le  to 
adopt  any  of  them  as  a  standard,  and  it  became  necessary  to  resort  to  evapora- 
tion, smelting,  etc.,  to  destroy  any  supposed  peculiar  combinations,  however 
well  convinced  /might  be  of  the  reliability  of  these  reagents  ) 

I  precipitated  a  sample  of  the  solution  by  sulphureted  hydrogen,  and 
obtained  gold  amounting  to  -0682  gram  per  liter.  I  could  obtain  no  more 
gold  from  the  solution,  and  concluded  that  the  precipitation  was  complete. 
This  precipitate  is  practically  free  from  foreign  matter,  except  a  little  sul- 
phur, which  separates  after  the  gold,  and  helps  to  collect  the  latter.  The 
quantity  of  sulpi.ur  would  be  greater  if  the  solution  contained  more  iron  and 
free  chlorine.  The  cost  of  this  method  is  difficult  to  estimate  precisely,  but 
it  need  not  be  much  greater  than  the  method  by  sulphate  of  iron,  perhaps 
no  greater. 


16 

Second.  "Does  charcoal  filtering  very  slowly  take  all  the  gold  out?" 
After  filtering  a  quantity  through  charcoal,  I  liave  not  found  any  gold 
re:;iaining  in  the  solution,  except  traces  proportionally  insignificant,  and  up 
to  a  certain  point  fail  to  detect  any.  I  have  not  been  able,  in  the  time 
allowed,  to  determine,  even  approximately,  the  limit  to  the  power  of  tlie 
charcoal  to  remove  gold,  etc.,  and  this  limit  will  depend  greatly  on  the  com- 
position of  the  liquid  at  different  times,  on  the  amount  of  iron,  free  chlorine, 
etc. 

Third.  ' '  Do  you  know  any  thing  which  will  cheaply  prevent  the  lime,  etc., 
from  precipitating  when  the  gold  is  precipitated  Ijy  sulpliate  of  iron  ?"  I 
tliink  of  notliing  practically  applicable,  at  present. 

Fourth.  "Does  sulpliate  of  iron  precipitate  all  the  gold  from  this  solu- 
tion along  with  or  without  lime,  etc.  ;  also,  after  filtration  through  charcoal, 
should  there  be  any  gold  unprecipitated,  will  sulphate  of  iron  then  precipi- 
tate it?"  If  sulphate  of  ironfalls  to  precipitate  the  gold  under  these  cir- 
cumstances it  must  be  due  to.  some  cliange  in  the  condition  of  the  solution, 
or  of  the  state  of  combination  of  tlie  gold  by  the  charcoal.  It  is  liighly 
improbable  that  any  such  change  can  occur  as  to  prevent  the  action  of  sulphate 
of  iron,  and  to  determine  tliis  point  definitely  it  is  necessary  to  continue  the 
filtration  until  the  al>sorption  by  the  charcoal  ceases  to  be  complete,  and  then 
test  tlie  action  of  sulphate  of  iron.  I  have  not  had  time  to  continue  it  so 
far,  but  on  adding  a  minute  quantity  of  chloride  of  gold  to  the  liquid  after 
passing  through  charcoal,  I  obtained  the  normal  result. 

By  precipitating  a  sample  of  the  original  solution  by  sulphate  of  iron,  I 
obtained  gold  amounting  to  "0685  gram  per  liter.  I  have  been  unable  to 
find  gold  remaining  in  the  solution,  and  conclude  that  the  precipitation  is 
omplete.  I  consider  the  quantity  obtained  as  identical  with  that  obtained 
by  sulphuretcd  hydrogen,  as  the  sample  used  was  only  a  fraction  of  a  litet 
(100  c.  c),  and  the  error  in  manipulating  this  quantity  of  gold  might  amounr 
to  the  difference,  which  was  less  than  one  twentieth  milligram.  The  action 
of  sulphate  of  iron  is,  first,  to  color  tlie  solution  purple  with  finely-divided 
gold.  Aft'jrward,  esp'jcially  when  agitated,  the  gold  aggregates  to  some 
extent,  and  the  solution  loses  its  color  ;  finally,  a  little  sulphate  of  lime  sep- 
arates and  subsides  with  the  gold.  If  the  solution  is  not  slightly  acidified, 
a  little  basic  salt  of  iron  will  separate  also. 

Fifth.  "Do  you  know  of  any  other  cheap  method  of  getting  all  the 
gold  without  lime,  etc.  ?"  A  solution  of  protochloride  of  iron,  made  by  dis- 
solving scrap  iron  in  muriatic  acid  may  be  used,  and  will  precipitate  the 
gold  without  lime,  and,  I  think,  in  a  state  of  great  purity.  The  cost  of  this 
would  be  probably  about  the  same  as  sulphate  of  iron. 

Very  respectfully, 

WILLIAM  E.  GIFFORD. 


17 

University  of  Pennsylvania,  | 

West  Philadelphia,  Feb.  13,  11  p.m.,  1883.  j 

R.  P.  RoTHWELX.,  Superintendent  : 

Dear  Sir  :  You  sent  me  about  1^  liters  of  liquid,  said  to  have  resulted 
from  the  chlorination  by  the  Mears  ijrocesa,  after  a  previous  roasting  of 
the  Canada  Consolidated  Gold  Mining  Company's  ore.  By  your  state- 
ment this  liquid  contains  per  liter  : 

Arsenic  acid  _  3  600 

Hydrochloric  acid  ^  5*880 

Sulphuric  acid        =  0-800 

Lime  =  0-900 

Ferric  oxide  =  0110 

Gold  =  0-057 

It  is  further  stated  that,  upon  adding  ferrous  8uli;)hate  to  this  liquid, 
an  unmanageable  voluminous  jirecipitate  will  form,  and  that  this  pre- 
cipitate is  gypsum,  containing  the  gold.  A  Iso,  that  a  preciijitate  of  lime 
and  magnesia  suli^hates  will  form,  when  sulphuric  acid  be  added  alone 
to  the  liquid.  A  sanijile  of  such  ijrecipitate  was  sent  me.  You  propose 
the  following  questions  : 

1st.  How  can  the  formation  of  the  \inmanageable  precipitate  be 
avoided  ? 

2d.  Does  this  precii^itate  carry  down  all  the  gold  with  it  ? 

3d.  Which  other  precipitant  might  be  iised,  so  that  it  would  not  take 
down  any  impurity  with  the  gold  ? 

In  order  to  find  answers  to  these  questions,  the  following  experiments 
were  made.  It  may  here  be  mentioned  that  a  larger  quantity  of  liquor, 
BO  that  one  liter  could  have  been  used  for  each  test,  would  have  lessened 
the  error  of  manipulation  ;  but,  even  as  it  is,  the  results  are  quite  trtist- 
worthy,  and  enable  us  to  base  technical  reasoning  thereupon  : 

First  Experiment, — To500cc.  of  the  liquor  were  added  10  cc.  of  dilute 
sulphuric  acid  =  1-73  gr. of  sulphviric  hydrate.  From  a  burette  was  dropped 
a  solution  of  1  crystallized  ferrous  sulphate  in  10  water.  After  the  addi- 
tion of  3-6  cc,  the  yellow  color  is  completely  discharged,  and  at  4  cc. 
the  liquid  fills  with  brown  jirecipitate  (gold).  No  precijjitate  of  gypsum 
was  noticed  for  thirty  minutes,  but  next  morning,  when  the  liquid  was 
quite  clear,  gypsum  had  crystallized.  It  was  all  brought  upon  a  filter, 
no  more  water  being  used  than  necessary  to  clean  the  beaker-glass.  After 
ignition  it  weighed  0-663  gr.  It  was  treated  with  aqua  regia  and  precip- 
itated by  HaS.  The  ignited  precipitate  weighed  36-3  mgr.  Packed  with 
borax  into  a  paper,  it  was  fused  to  a  button,  flattened  upon  the  anvil, 
and  weighed  34-5  mgr.  of  fine  gold.  By  the  equation  (AuCls)^  +  (Fe 
SO4).  =  Aua  + (re.S30,a)3+ (HC1)„,  -392  gold  require  1668  parts  of 
cry  St.  iron  suli)hate;  34-5  mg.  Au  therefore  34-5  x  4-25  =  146-6  mgr.  In 
the  above  4  cc.  there  are  contained  400  mgr.  of  sulphate,  nearly  2  -7  times 


18 

the  required  quantity.  It  will  be  noticed  that  this  experiment  yielded 
69  mgr.  of  Au  per  liter,  against  57,  as  given  in  the  analysis.  Sulphide 
of  hydrogen  added  to  the  filtrate  gave  no  browning,  but  only  opalescent 
yellow  after  a  few  minutes  (arsenic). 

Second  Exjm'iment. — To  250  cc.  of  the  liquor  was  added  from  a 
burette  a  fresh  saturated  aqueous  solution  of  hydrogen  sulphide.  The 
yellow  color  disappears  after  the  addition  of  1  cc.  Then  a  brown  color 
appears,  and  at  4  cc.  the  color  in  reflected  light  is  nearly  black.  Stirring 
vigorously  coagulates  the  gold  sulphide.  To  be  sure  of  a  sufficiency,  6 
more  cc.  were  added — 10  in  all.  After  thirty  minutes,  the  liquid  was  still 
very  brown  in  transmitted  light  from  numerous  floating  particles  ;  only 
50  cc.  were  passed  through  a  filter  (filtrate  absolutely  colorless  and 
unchanged  by  more  than  H-iS)  ;  the  bulk  was  left  standing  over 
night,  to  see  how  far  a  complete  settling  would  take  place.  In  the 
morning,  after  fourteen  hours'  standing,  the  liquid  was  still  brown, 
nearly  as  much  as  the  evening  before.  Settling  could  not  be  relied  upon, 
and  filtration  is  necessary.  After  collecting  the  precipitate  upon  filter, 
(double  paper  always  used),  it  was  washed  with  about  40  cc.  of  wuter, 
containing  a  few  drops  of  dil.  HCl.  By  ignition  obtained  20  mgr,  fused 
to  a  button  with  borax  and  cleaned  by  flattening,  weighed  18  2  mgr, 
equal  to  72  '8  mgr  j-ier  liter,  against  57  mgr  of  the  analysis,  and  69  mgr  by 
previous  experiment. 

Third  Expm-hnent. — To  250  cc.  of  liquor  added  first  3  cc.  of  dilute 
HCl.  (1  in  10);  then  the  O'l  ferrous  sulphate  from  a  burette.  After  the 
yellow  color  x  is  faded,  a  dirty  white  flocculent  precipitate  begins  to 
form,  which  rapidly  ass.imes  a  deep  blue  purple  color  on  addition  of  a 
second  cubic  centimeter.  The  end  of  the  reaction  can  not  be  noted 
here  as  well  as  in  preceding  experiments.  But  since,  in  Exp.  1,  4  cc. 
had  been  sufficient  for  J  liter,  I  added  here  2  cc.  for  J  liter.  The 
greater  part  of  this  precipitate  settles  rapidly  ;  the  liquid,  however, 
retains  its  jDurple  color  from  suspended  particles.  Consistency  of  precip- 
itate is  very  fine,  compact,  flocculent.  After  four  hours'  standing,  the 
liquid  was  as  purple  as  after  the  first  half- hour.  It  filters  very  easily 
through  a  double  jiaper.  When  all  was  collected,  I  washed  with  about 
50  cc.  of  water  ;  then  I  filled  the  filter  with  10  cc.  of  0-1  hydrochloric 
acid  (cold),  and  a  yellow  liquid  ran  from  the  filter,  while  the  latter  cov- 
ered itself  with  brown  gold.  Washed  once.'then  put  on  10  cc  more  of 
O'l  hydrochloric  acid,  and  finished  by  washing  with  50  cc.  of  cold 
water.  Ignited  precipitate  and  ashes  weighed  19*2  mgr.,  fused  to  a 
button  weighed  18 '8  mgr.,  the  highest  result  of  the  three  experiments.  I 
am  not  certain  that  this  button  Avas  quite  fine  ;  it  may  contain  a  small 
quantity  of  arsenic,  and  it  will  yet  be  assayed  for  purity.  But  certainly 
this  trial  gave  as  much  gold  as  the  hydrogen  sulphide.  I  attribute  that 
mainly  to  the  nature  of  the  vehicle  inclosing  the  gold  and  leaving  less 


19 

chance  for  a  mechanical  loss,  sticking  to  glass  surface  or  passing  through 
filter-paper. 

In  the  acid  filtrate  from  tlic  gold  I  found — 

Arsenic  acid  —■  0-0588  gr. 

Ferric  oxide  —  0  0340  gr. 

Calcium  sulphate  =  0  00G5  gr. 

We  have  here  the  atomic  ratio  of  AsjOs  :  FcaOs  =  50:  4-25,  that  is,  a 
true  basic  iron  arseniate,  mixed  witli  about  7  per  cent  of  gypsum.  This  is 
the  composition  of  the  precipitate  I  anticipated  when  you  wrote  that  it  was 
chiefly  a  mixture  of  lime  and  magnesia  sulphate.  This  observation  is  of  con- 
siderable scientific  interest.  We  iidve  here  a  true  iron  purple  of  cassius  ;  that  is, 
this  purple  is  not  a  chemical  combination  of  stannic  hydrate  and  gold,  but  a 
mere  mechanical  mixture  ;  it  requires  only  an  enveloping  white  flocculent 
vehicle  to  bring  out  the  metallic  gold  with  a  purple  color.  I  reserve  the 
right  to  make  a  public  announcement  of  this  observation.  The  precipitate 
can  only  form  in  a  perfectly  neutral  or  Jicarly  neutral  solution,  such  as 
your  liquor  is.  By  these  experiments,  I  believe  that  the  two  first  questions 
have  been  satisfactorily  answered.     But  of  this  anon. 

It  remained  now  to  determine  how  thorough,  ly  each  precipitant, the  gold 
will  be  removed  from  the  solution.  A  solution  was  required  as  nearly  as  pos- 
sible like  the  one  in  question,  containing  a  known  quantity  of  gold.  Accord- 
ingly four  liters  were  made  of  such  a  liquid  by  the  analysis,  although  there 
were  some  grave  douljts  regarding  its  accuracy.  For,  if  we  calculate  the 
acids  and  oxides  as  to  their  combining  weights,  it  follows  that  CaO  :  AsaO. 
as  3'8  :  1"1,  as  4  :  1,  which  is  chemically  impossible.  The  ratio  should 
be  as  1  :  1.    This  was  proved  by  the  fact. 

Solution:  12'2  grs.  of  white  arsenic  were  oxidized  by  aqua  regia, 
evaporated  to  dryness,  60  grs.  of  marble-dust  dissolved  in  IICl,  and  boiled 
so  that  a  residue  remained;  7"2  gr.  magnesium  carbonate  likewise.  0'3l 
gr.  metallic  iron  oxidized  and  evaporated,  and  5  cc.  of  the  dilute  sul- 
phuric acid  added.  When  the  iron  and  arsenic  acids  came  together,  they 
precipitated,  and  HCl  had  to  be  added  to  maintain  solution.  The  gypsum 
dissolved  completely  in  3  liters  of  water  :  240  mgr.  of  fine,  precipitated  gold 
were  then  dissolved  and  mixed  with  the  other  ingredients,  so  that  the  whole 
measured  just  4  liters.  In  one  liter  there  is,  hence,  60  mgr.  of  gold.  The 
color  of  solution  is  light  yellow,  not  the  rich  brown  yellow  of  the  solution 
you  sent.  I  do  not  know  at  present  the  cause  for  this  difference,  unless  it  be 
the  greater  neutrality  of  the  latter,  caused  by  the  pressure  in  the  chlorinator. 
This  must  be  the  cause,  because,  with  my  solution,  I  could  not  obtain  the 
purple  precipitate. 

The  following  tests  were  made : 

Fourth  Experiment. — To  500  cc.  of  solution  were  added  3  cc.  of  con- 
cent, hydrochloric  acid,  and  10  cc.   of  01  ferrous  sulphate.      Did  at  first 


20 

not  socin  to  precipitate ;  but  8taiulin<^  over  night,  a  brown  sediment  was 
oliservecl.  Filtered  and  waslied  witli  40  cc.  of  water,  and  3  of  TO  IICl. 
Ignited,  weighed  ;il8"»  mgr.  ;  fused  with  borax,  the  buttou  weighed  27-7 
instead  of  JJO  iikji'. 

Fifth  Ki-pei-i7netif.— To  5(H)  cc.  of  .solution  w(M'e  added  6  cc.  of  ferroxiH 
solution  and  no  acid  whatever.  Liijuid  bcciune  colorlcHs  when  2  cc.  had 
been  dropped  into,  and  brownish  turbid  when  4  iiad  boon  added. 
Total  equals  6  cc.  Aftcn-  waHhing  with  water  without  acid,  the  ignited 
precipitate  weighed  HO-Omgr. ;  fused  with  borax,  the  button  weighed 
27-85  nigr. 

Si.rth  Expei'iineiit.—'Ho  500  cc.  of  solution  added  5  cc.  of  fresh  satu- 
rated chlorine  water.  The  mixture  smelled  very  strongly  of  chlorine. 
Upon  the  addition  of  4  cc.  ferrous  solution,  color  disajipeared.  But  even 
after  adding  40  cc.  of  fcrrons  solution  iu  all,  no  turbidity  was  visible. 
Stood  twenty  hoii?'s.  Now  the  gold  could  be  seen  among  the  crystals  of 
gypsum,  of  which  about  O-,")  gr.  had  falhui  out  ;  it  dissolved  in  250  cc. 
of  water.  Ignited,  the  precipitate  weighed  304  mgr. ;  the  button,  fused 
with  borax,  weighed  28  4  mgr.  '  The  jiresence  of  free  chlorine,  nor  the 
addition  of  large  excess  of  ferrous  sulphate,  interferes,  therefore,  with 
the  i)reci2)itation  of  the  gold. 

Seventh  Krjmriineiit. — To  500  cc.  of  solution,  at  a  temperature  of  10**  C. 
were  added  6  cc.  of  fresh  saturated  solution  of  HjS.  Precii)itate  does 
not  coagulate  so  rapidly  as  when  previously  the  teini)erature  had  been 
about  17**  C.  It  stood  twenty  hours,  had  settled  comijletely  and  filtered 
well.  In  the  perfectly  colorless  filtrate,  HjS  cansed  no  coloration. 
Ignited,  the  preciiiitatc  weighed  38  8  mgr.;  the  button,  fused  with 
borax,  weighed  29  85  mgr.,  instead  of  30  mgr. 

Eighth  Experiment. — To  500  cc.  of  solution  added  6  fc.  of  chlorine- 
water  and  14  cc.  of  solution  HjS,  was  allowed  to  stand  for  two  hours, 
then  filtered,  the  great  bulk  having  settled  in  flocculont  state.  Precipi- 
tate ignited  gave  34.4  mgr  ;  the  fused  button  weighed  29 15  mgi".  instead 
of  30  mgr. 

NoTB.— There  Is  rcaHoii  to  believe  that  a  loss  occurred  in  the  fusing  operation. 

Now,  it  seems  to  me  clearly  proved  that  sulphide  of  hydrogen  precip- 
itates the  gold  completely  (Experiment  Seven),  and  that  the  purple  pre- 
cipitate gave  a  higher  result  even  than  the  suliihide  of  hydrogen,  which 
I  only  attribute  to  the  mechanical  condition  of  the  precipitate.  Sul- 
phide of  hydrogen  takes  down  no  impurities  if  applied  in  proper  quan- 
tity, which  is  best  done  when  water  is  charged  with  that  gas.  Acid  is 
required  to  make  HaS  and  acid  also  to  decompose  the  purple.  The 
latter  offers  better  guarantee  against  loss,  and  reqiiires  no  special  appa- 
ratus. It  will  work  with  your  solution,  becau.so  this  is  very  neutral.  If 
not  more  of  the  iron  saltis  atlded  than  necessary,  no  gypsum  of  any  con- 
sequence will  fall  out.     Any  workman  of  average  intelligence  can  readily 


21 

Tip  trained  to  perform  the  w  -)rk.  L(>t  him  tiike  a  liter  of  the  liquor  after 
the  latter  iH  thoroughly  mixed  in  tlio  tank.  Have  the  cojjperaH  dissolved 
1  in  10  water,  and  let  him  add  from  u  burette  until  the  purple  forms, 
then  lot  him  pour  some  of  liquid  upon  a  double  filter,  and  try  with  HjS 
water,  if  a  browning  occurs  ;  if  not,  he  has  added  enough  of  the  iron  salt; 
if,  thou  he  adds  a  f(iw  drops  more.  This  operation  will  not  take  more 
than  ton  minutes.  If  now  the  iron  solution  bo  in  a  cylindrical  tank,  with 
a  .rod  in  it  graduated  to  one  quarter  liters,  he  cau  let  in  the  proper 
(piantity  into  the  precii)itiite  tank  without  any  troul)le.  To  decompose  the 
purple,  you  use  warm  one  tenth  sulphuiic  acid,  and  less  acid  will  be 
required  than  if  dry  hydrogen  sulphide  be  generated  for  the  purpose. 
I  do  not  advocate  this  plan  as  a  i)ot  one,  because  the  sul})hide  of  hydro- 
gen is  equally  good,  but  recjuires  the  attendance  on  a  special  api)aratus. 
Shotild  you  decide  upon  the  latter  method,  I  Avould  advise  the  use  of 
satiirated  water,  which  yoii  get  by  fitting  a  good-sized  iron  stovepipe, 
barred  inside  and  outside  twenty  feet  high,  filled  with  coke  of  nut  size, 
over  which  the  water  trickles  against  the  current  of  the  gas.  If  there  be 
no  free  chloi-ine  or  only  little,  six  liters  per  500,  or  twelve  jjer  cubic 
meter,  will  be  quite  sufficient.  But  the  attendant  will  have  to  test  a  liter 
exactly  as  before  with  the  iron  solution  ;  and  good  stirring  is  retpiired. 
If  yoii  desire,  I  will  furnish  you  with  a  detailed  diagram  and  measures 
for  the  ajjparatus,  as  I  should  build  it.  But  you  must  let  mo  know  the 
daily  production  in  liters. 

To  do  any  thing  with  the  roasted  ore,  I  have  noi,  had  time  to  attend 
to  that  yet.  I  shall  continue,  also,  my  experiments  from  a  scientific 
stand-point,  operating  with  larger  quantities,  to  get  a  ;  et  truer  value  of 
ferrous  sulphate  versus  HaS. 

Your  telegram  asking  for  my  results  to-day  Avas  received  at  noon. 
But  having  to  attend  to  teaching  duties,  I  could  not  ^vrite  down  my 
notes.     Yoiirs  truly, 

Geokge  a.  Konig,  Ph.D., 

Prof,  of  Metallurgy. 

P.  S. — No  elevation  of  temjierature  was  made  use  of  in  any  of  thoi 
experiments.  The  action  of  SOj  was  not  mentioned,  because  it  acts 
with  satisfaction  only  at  the  boiling-ijoint.  The  filtrates  were  always 
tested  for  gold. 


New  Yobk,  February  7,  1883. 
R.  P.  RoTHWKLL,  Superintendent : 

Sib: 

Fh'st  Sdviple. 

One   ton   of  liquor  equal   to  31  "7   cubic    feet   of    liquor,   contains, 
according  to  evfl()oration  lest,  194  ounce  gold,  equal  to  $40.19  (equal  to 


22 

66-5  gramH  gold  per  1000  kilos  liquor).  By  precipitation  with  sulphureted 
hydrogen,  from  crude  solution,  2  ounces  gold,  equal  to  $41.34  (pqual  to 
68  56  grams  per  1000  kilos),  can  be  extracted. 

Second  Sample. 

One  ton  of  liquor  gives  2 '19  ounces  (75 '07  grams)  gold,  equal  to  $45.96, 
by  precipitation  with  sulphate  of  iron  ;  and  1'95  ounces  (66 '84  grams) 
gold,  equal  to  $40  30,  by  precipitation  with  sulphate  of  iron  from  a 
boiled  solution  ;  and  2-43  ounces  (equal  to  83-29  grams)  gold,  equal  to 
$50.23,  by  jirecipitation  with  sulphureted  hydrogen  from  the  cold 
solution. 

Slight  inconsistencies  above  to  be  noted,  are  to  be  placed  to  the 
account  of  "limit  of  accuracy." 

OUSEIIVATIONS. 

1.  Sulphate  of  iron  does  not  precipitate  all  the  gold,  especially  not  if  tlic 
solution  still  contained  some  fioe  chlorine.  Evaporation  test  showed  gold 
still  present  in  precipitated  liquor. 

2.  Beltling  and  filtration  are  very  slow,  perfect  filtration  almost 
impossible. 

3.  Cost  about  the  same  as  sulphureted  hydrogen. 

4.  Gold  is  mixed  with  some  lime,  but  more  alumina,  and  product  is 
difficult  to  melt. 

5.  Sulphureted  hydrogen  precipitates  the  gold  perftctly,  quickly,  and 
in  a  floccular  state,  making  filtration  easy.  The  gold  is  pure  sulphuret,  with 
possibly  a  little  sulphuret  of  arsenic,  and  easily  smelts  to  pure  gold.  After 
filtration,  the  solution  can  be  saturated  with  sulphureted  hydrogen,  and  thus 
a  heavy  percentage  of  beautiful  sulphuret  of  arsenic  (auri  pigii.ent)  obtained, 
which  may  possibly  pay  for  the  entire  operation. 

Test  in  filtering  through  charcoal  and  electrical  test,  and  estimate  of 
cost  will  follow  to-morrow. 

Solution   contains    but    very  little    lime.      The   alkaline    earth    is 

alumina.   (Probably  as  a  lime,  iron  and  magnesia  alum,  or  even  arseniate. ) 

The  analysis  shown  must  be  wrong.     In  sample  No.  1  the  percentage 

of  gold  is  but  0-006  per  cent ;  in  sample  No.  2,  0-0075  per  cent ;  while 

the  French  analysis  calls  for  per  ton  of  liquor. 

Very  respectfully, 

MATHEY  &  RIOTTE. 


New  Yobk  Feb.  14,  1883. 

Sib  :  I  have  just  completed  the  experiments  with  the  gold  solution, 
and  the  ijossibility  of  precipitating  by  electricity.  I  made  two  trials. 
One  to  collect  the  gold  on  the  anode  pole  in  a  bath  of  mercury,  and 
another  to  simply  precipitate  in  the  solution. 


S3 

The  first  trial  gave  results  that  were  very  accurate,  but  too  much 
time  was  required.  The  little  gold  amalgam  was  easily  handled,  and 
the  solution  needed  no  filtering. 

The  second  trial  was  made  with  a  porous  cup  and  platin  wire  anode. 
The  gold  was  quickly  precipitated,  but  the  collection  necessitates  fil- 
tering, or  decantatiori  and  filtering,  and  the  gold  is  in  a  very  fine  state. 

Taking  the  different  methods,  I  should  say  that  the  choice  fell 
between  two— precipitation  with  sulphureted  hydrogen  (generated  from 
paraflSne  and  sulphur),  and  by  means  of  a  dynamo. 

The  plant  for  the  first  is  very  inexpensive,  the  cost  of  sulphur  and 
paraffine  nominal,  and  the  possibility  of  making  the  by-products  (realgar) 
profitable  good  ;  filtering  easy  and  perfect.  The  cost  of  a  dynamo  is  at 
least  $1000.  Eunning  cost  very  little,  but  filtering  and  collection 
difficult. 

I  should  counsel  you  to  make  a  trial  with  sulphureted  hydrogen 
before  all  others.  Very  respectfully, 

E.  N.  EIOTTE     or 

MaTHEY  &   ElOTTE. 


